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Manual of the New Zealand Flora.
18. Deyeuxia, Clarion
18. Deyeuxia, Clarion.
Annual or perennial grasses. Leaves flat or involute; ligules membranous. Spikelets small, 1-flowered, arranged in effuse or contracted or spike-like panicles with capillary whorled branches; rhachilla disarticulating above the 2 outer glumes, produced beyond the flower into a silky bristle. Glumes 3; 2 outer equal or sub-equal, persistent, empty, keeled, acute, not awned, usually 1-nerved; 3rd or flowering glume shorter than the empty glumes or equalling them, thin and hyaline or rigidly membranous or almost coriaceous, 5-nerved, entire or 2–4-dentate, callus at the base silky; awn generally present, straight or twisted, inserted above or below the middle of the glume. Palea more than half as long as the flowering glume or almost equalling it, thin, 2-nerved or 2-keeled. Stamens 3. Styles distinct, short; stigmas plumose. Grain oblong or obovoid, enclosed w thin the flowering glume and palea.
Species over 100, widely dispersed through the temperate regions of both hemispheres, particularly abundant in Andine South America. It is not at all easy to separate Deyeuxia from the allied genera Agrostis and Calamagrostis, and of late many authors, including Hackel, have placed the majority of species under the latter genus. It appears to me, however, that there is much to be said in favour of the arrangement, proposed in Hooker's "Flora of British India" (Vol. vii., p. 253), where Agrostis is limited to species in which the rhachilla is not produced at the back of the flower, and in which the callus of the flowering glume is naked or nearly so, Calamagrostis containing those in which there is also no prolongation of the rhachilla, but which have the callus villous with long hairs, while in Deyeuxia the species have both an elongated rhachilla and hairy callus. Understood in this sense, there are 7 New Zealand species of the genus, 3 of which extend to Australia and Tasmania, the remaining 4 being endemic.
| Spikelets 1/12–⅛ in. Flowering glume silky, truncate, minutely 4-denticulate; awn from the middle of the back | 1. D. Forsteri.page 868 |
| Spikelets ⅕–¼ in. Flowering glume silky at the base only, 2 lateral nerves produced into short awns, dorsal awn from below the middle of the back | 2. D. Billardieri. |
| Slender, 4–12 in. Leaves filiform. Panicle 1–2½ in. Spikelets ⅛ in. long; callus-hairs very long | 3. D. setifolia. |
| Slender, 9–36 in. Leaves narrow, involute. Panicle 2–5 in. Spikelets ⅙–¼ in.; awn from below the middle, exserted; callus-hairs short. Rhachilla obviously produced | 4. D. avenoides. |
| Tall, slender, 2–4 ft. Leaves flat, ⅙–¼ in. broad. Panicle 4–6 in. Spikelets ⅙–¼ in.; awn short, almost terminal. Rhachilla obviously produced | 5. D. Youngii. |
| Tall, stout or slender, 1–3 ft. Leaves flat or involute. Panicle 2–6 in. Spikelets ⅛ in.; flowering glume 4-cuspidate; awn from near the base. Rhachilla not produced or very obscurely so | 6. D. quadriseta. |
| Slender, 1–3 ft. Leaves flat, flaccid. Panicle 3–6 in., lax but narrow. Spikelets ¼–⅓ in.; callus-hairs long; awn from about the middle. Rhachilla obviously produced | 7. D. Petriei. |
| 1. | D. Forsteri, Kunth, Rev. Gram. i. 77.—Annual or rarely perennial, very variable in size and habit. Culms tufted, erect or decumbent at the base, slender, smooth, 2–4-noded, 6–24 in. high. Leaves shorter than the culms, very narrow and involute or broader and flat, 1/12–⅙ in. diam., almost glabrous or scaberulous on the margins and principal veins; sheaths smooth, grooved, the uppermost usually long; ligules long, narrow, membranous. Panicle 3–12 in. long, usually very lax and spreading when mature, but contracted in the young state; branches in distant whorls or clusters, the lowermost 2–6 in. long or more, repeatedly trichotomously divided, finely capillary, scabrid; pedicels very slender. Spikelets numerous, pale-green, 1/12–⅛ in. long. Two outer glumes subequal, lanceolate, acuminate, membranous, 1-nerved, keel scabrid; 3rd or flowering glume ⅓–½ shorter, oblong, truncate, minutely 4-denticulate, hyaline, more or less silky on the sides and with a tuft of hairs at the base; awn from the middle of the back, slender, straight or bent. Palea narrow-linear, bifid at the apex. Rhachilla usually produced behind the palea as a short silky bristle, but often very small and hardly perceptible.—Hook. f. Fl. Nov. Zel. i. 298; Benth. Fl. Austral. vii. 579. Avena filiformis, Forst. Prodr. n. 46. Agrostis avenacea, Gmel. Syst. i. 171. A. Forsteri, Roem. and Schult. Syst. ii. 359; A. Rich. Fl. Nouv. Zel. 131; A. Cunn. Precur. n. 253; Raoul, Choix, 39. A. æmula, R. Br. Prodr. 172; Hook. f. Handb. N.Z. Fl. 329; Buch. N.Z. Grasses, t. 21. A. Solandri, F. Muell. Veg. Chath. Isl. 60.
North and South Islands, Stewart Island, Chatham Islands: Abundant throughout. Sea-level to 3000 ft. Var. pilosa, Cheesem.—Coarser and more robust. Leaves broader, ¼–⅓ in. or even more, flat. Spikelets slightly larger.—D. pilosa, Buch. Man. |
N.Z. Grasses, 6. Agrostis pilosa, A. Rich, Fl. Nouv. Zel. 134, t. 23 Raoul, Choix, 39; Hook. f. Fl. Nov. Zel. i. 297 Handb. N.Z. Fl. 329; Buck. N.Z. Grasses, t. 22.
North and South Islands Damp subalpine localities, not uncommon. Hardly more than a luxuriant state of the type.
Var. semiglabra, Hack. MS.—Flowering glume glabrous on the back, its callus sparingly pilose. Otherwise as in the type.
North and South Islands Not uncommon.
Var. humilior, Hack. MS.—Root often perennial. Culms 3–10 in. high. Panicle very broad and spreading; branches few, distant, binate, few-flowered. —A. striata, Col. in Trans. N.Z. Inst. xxi. (1889) 107.
North and South Islands: Probably not uncommon in mountain districts, Lake Waikaremoana, Hill! Clarence Valley, Lake Tennyson, Broken River. Tasman Valley, &c, T. F. C.;Lake Te Anau, Petrie!
Var. littoralis, Hack. MS.—Root annual. Culms 2–9 in., often forming a compact sward. Panicle rather narrow, contracted, many-flowered. Empty glumes linear-lanceolate, narrower than in the type.
Kermadec Islands, North and South Islands Rocky or gravelly places near the sea, not uncommon.
Var. Lyallii, Hack. MS.—Culms 6–12 in. Leaves narrow, involute. Panicle lax branches few, binate or ternate. Spikelets larger, ⅛–⅙ in. long. Flowering glume densely clothed with silky hairs.—A. Lyallii, Hook. f. Fl. Nov. Zel. i. 297.
South Island:Near Westport, Townson!Okarito, A.Hamilton! Jackson's Bay, Kirk! Milford Sound, Lyall, Kirk! Catlin's River, Petrie! Auckland Islands: Kirk!
Var. micrathera, Hack. MS.—Habit of var. Lyallii, but larger and leaves broader. Spikelets still larger, ⅕–¼ in. long. Empty glumes linear-lanceolate, acuminate. Flowering glume short, ½as long as the empty glumes, very thin, sparingly silky; awn from above the middle, short, delicate, hardly exserted beyond the empty glumes.
Antipodes Island, Campbell Island Kirk! Possibly the same as Agrostis leptostachya,Hook. f. Fl. Antarct. i. 94, but I have not seen an authenticated specimen, and it is described as having no palea and a long awn.
D. Forsteri is one of the most generally diffused plants in New Zealand, and is certainly one of the most variable. In attempting to characterize its chief forms, I have mainly followed the grouping suggested to me by Professor Hackel, who has kindly examined sets of all the varieties contained in my herbarium. The species is as plentiful in Australia and Tasmania as in New Zealand.
| 2. | D. Billardieri, Kunth, Rev. Gram. i. 77.— Culms tufted, usually rather stout, erect or decumbent at the base, 9–18 in. high, leafy throughout. Leaves shorter than the culms, ¼–½ in. broad, flat, striate, usually scabrid on the margins and veins; sheaths rather narrow, rough, the uppermost very long, usually enclosing the culm up to the base of the panicle; ligules long, membranous, lacerate. Panicle 4–12 in. long, very broad and lax, often as broad as long when fully expanded branches numerous, in regular whorls, long, capillary, scabrid, trichotomously divided pedicels thickened page 870at the tips. Spikelets ⅕–¼ in. long, green or purplish. Two outer glumes slightly unequal, narrow-lanceolate, acuminate, 1-nerved or 3-nerved with the lateral veins very short, scabrid on the keel and sides; 3rd or flowering glume ¼–⅓ shorter, oblong, truncate, silky at the base, 5-nerved, the 2 lateral nerves produced on each side into short awns, the 2 outer of which are longer than the 2 inner; dorsal awn from below the middle, straight or bent, usually exceeding the spikelet. Palea about ⅔ as long as the flowering glume, linear, 2-nerved. Rhachilla produced into a silky bristle almost as long as the palea.—Hook. f. Fl. Nov. Zel. i. 298 Benth. Fl. Austral. vii. 580. Agrostis Billardieri, R. Br. Prodr. 171; A. Rich. Fl. Nouv. Zel. 130; A. Cunn. Precur. n. 252; Raoul, Choix, 39; Hook. f. Handb. N.Z. Fl. 329; Buch. N.Z. Grasses, t. 23.
Var. tenuis, Petrie, MS.—Smaller and much more slender. Leaves narrow, involute. Panicle smaller, with fewer branches. Spikelets rather smaller. North and South Islands, Chatham Islands: Abundant throughout in rocky or sandy places near the sea. Inland at Te Aroha, Upper Thames Valley. Var. tenuis: Catlin's River, Otago, H. J. Matthews. Easily distinguished from D. Forsteri by the stouter habit and broader leaves, large spikelets, and by the more glabrous flowering glume, the lateral nerves of which are excurrent as short awns. It is a common Australian and Tasmanian plant. |
| 3. | D. setifolia, Hook. f. Fl. Nov. Zel. i. 299, t. 65B.—Culms tufted, slender, wiry, smooth, 4–12 in. high. Leaves shorter than the culms, narrow, setaceous or filiform; sheaths smooth, striate, the uppermost long, tight; ligules oblong, membranous. Panicle erect, 1–2½ in. long, ⅕–⅓ in. broad, narrow, contracted; branches few, short, erect, scaberulous, sparingly divided. Spikelets few, pale-green, ⅛ in. long; pedicels short, scabrid. Two outer glumes subequal, oblong-lanceolate, acuminate, firm, spreading, keeled, 1–3-nerved, the lateral nerves usually short, keel scabrid; 3rd or flowering glume ¼–⅕ shorter, hard and almost coriaceous, silky at the base, the hairs almost as long as the glume, truncate and minutely 4-toothed at the tip; awn from the middle of the back, stout, scabrid, recurved, longer than the spikelet. Palea almost as long as the flowering glume, linear-oblong, 2-nerved. Rhachilla produced into a silky bristle half as long as the palea or more.—Agrostis setifolia, Hook. f. Handb. N.Z. Fl. 329; Buch. N.Z. Grasses, t. 24B.
North and South Islands, Stewart Island: Not uncommon in mountain districts from the East Cape and Mount Egmont southwards. 3000–5000 ft. Allied to the following species, but a much smaller plant, panicle smaller and more slender, spikelets not much more than half the size, and flowering glume much more silky at the base and broadly truncate at the tip. page 871 |
| 4. | D. avenoides, Buch. Man. N.Z. Grasses, 6.—Culms tufted, erect, slender, rigid, smooth, 9–24 in. high. Leaves much shorter than the culms, narrow, in slender forms almost filiform, smooth, strongly involute; sheaths smooth, deeply grooved, the uppermost long; ligules short, broad. Panicle erect, 2–5 in. long, ¼–½ in. broad, narrow, contracted, usually dense; branches short, erect, sparinglydivided. Spikelets pale-green, ⅕–¼ in. long; pedicels shorter than the spikelets. Two outer glumes subequal, lanceolate, acuminate, sharply keeled, rigid, 1-or rarely 3-nerved, keel scabrid, sides smooth or minutely rough; 3rd or flowering glume slightly shorter, bard, convolute, scabrid, slightly silky at the base, minutely 2–4-cuspidate; awn from below the middle, stout, recurved, twisted below the bend, longer than the spikelet. Palea almost as long as the flowering glume, linear, hyaline, 2-nerved. Rhachilla produced into a silky bristle nearly ½ as long as the palea.—Agrostis avenoides, Hook. f. Handb. N.Z. Fl. 330 Buch. N.Z. Grasses, t. 24A.
Var. brachyantha, Hack. MS.—Culms taller and more slender, 1–3 ft. high. Leaves narrower, filiform, often strict and wiry. Spikelets smaller, about ⅙ in. long rhachilla shorter and more delicate. North akd South Islands, Stewart Island: Var. brachyantha common throughout, ranging from sea-level to 3500 ft., the typical state apparently confined to mountain districts in the South Island. Nelson-Wairau Gorge, T. F. C.Canterbury— Craigieburn Mountains, Petrie!Rangitata Valley, Sinclair and Haast; Tasman Valley, T. F. C. Otago—Not uncommon in upland districts, Hector and Buchanan! Petrie! Cockayne! The typical state is well characterized by its large spikelets, which no doubt induced Hooker to give it the name of avenoides; but the var. brachyantha is an exceedingly puzzling form. Professor Hackel has no hesitation in placing it under D. avenoides, but most New Zealand botanists, including myself, have been accustomed to regard it as a state of D. quadriseta, to which it seems to show a very near approach, principally differing in the rather larger spikelets, with the rhachilla always produced at the back of the palea. It appears to me to be very much a matter of taste whether it should be placed under D. avenoides or D. quadriseta. |
| 5. | D. Youngii, Buch. Man. N.Z. Grasses, 6.—"Similar in habit to A. avenoides, but larger, 2–4 ft. high, more robust. Leaves flat, ⅙–¼ in. diam. Panicle 4–6 in. long, very slender, flexuous branches very short. Spikelets ⅙–¼ in. long. Empty glumes oblong-lanceolate, acuminate, rigid, smooth, glabrous, nerveless flowering glume as long, pedicelled, hard, scabrid, 2–4-cuspidate; awn very short, almost terminal. Palea as long as the glume; pedicel stout, with long silky hairs."—Agrostis Youngii, Hook. f. Handb. N.Z. Fl. 330; Buch. N.Z. Grasses, t. 25.
South Island: Canterbury—Dry hillsides, sources of the Waitaki River, Haast. page 872This is unknown to me, and I have therefore reproduced Hooker's description. It appears to differ from all forms of D. avenoides in the short "almost terminal" awn. Professor Hackel suggests that it may be a variety of D. quadriseta, but the large spikelets and produced rhachilla hardly support such a view. |
| 6. | D. quadriseta, Benth. Fl. Austral. vii. 581.—Culms tufted, erect, stout or slender, smooth or rather rough, 1–3 ft. high. Leaves much shorter than the culms, variable in width, sometimes ⅛ in. broad and quite flat, at other times verynarrow and setaceous or filiform, often involute, glabrous or minutely scaberulous; sheaths smooth or rough, grooved; ligules oblong, membranous. Panicle 1 ½–6 in. long, very narrow and spike-like, dense, cylindric, rarely broader and obscurely lobed, pale-green or brownish-green, shining; branches numerous, short, erect, branched from the base. Spikelets small, about ⅛ in. long, shortly pedicelled. Two outer glumes subequai, lanceolate, acuminate, keeled, keel minutely scabrid, slightly hairy at the base, tip minutely but distinctly 4-awned; dorsal awn attached below the middle, sometimes almost basal, usually not much longer than the outer glumes. Palea almost as long as the flowering glume, narrow, 2-nerved. Ehachilla either not at all produced at the back of the palea or very obscurely so. —Agrostis quadriseta, R. Br. Prod. 171; Hook. f. Fl. Nov. Zel. i. 296; Handb. N.Z. Fl. 330; Buch. N.Z. Grasses, t. 26. Avena quadriseta, Labill. Pl. Nov. Holl. i. 25, t. 32.
North and South Islands, Stewart Island: Not uncommon throughout. Sea-level to 2500 ft. Also abundant in Australia and Tasmania. The rbachilla is seldom produced at the back of the palea, so that the plant technically falls into Agrostis.But it is so closely allied, to D. avenoides, which is an undoubted Deyeuxia, that I have decided to leave it in that genus. |
| 7. | D. Petriei, Hack, in Trans. N.Z. Inst. xxxv. (1903) 380 (sub. Calamagrostis).—Culms slender, erect, terete, 1–3 ft. high, glabrous, 3-noded, uppermost node near the middle of the culm. Leaves much shorter than the culms, about ⅛ in. broad, flat, rather flaccid, smooth or scaberulous on the upper surface; sheaths terete, close, scaberulous; ligules oblong, obtuse. Panicle 3–6 in. long, narrow but not very dense; rhachis smooth; branches short, binate or ternate, the lowermost often distant, short, erect, sparingly divided; pedicels shorter than the spikelets, smooth. Spikelets ¼–⅓ in. Jong, pale-green. Two outer glumes subequal, narrow-lanceolate, acute, rigidly membranous, 1-nerved, scabrid on the keel; 3rd or flowering glume about ⅙ shorter, lanceolate, subacute, minutely denticulate at the tip, firm but membranous, scabro-punctate on the back, callus with silky hairs ⅓ the length of the glume; awn inserted about the middle of the back, straight, equalling the empty glumes or rarely exceeding them. Palea almost as long as the flowering glume, page 873linear, bidentate. Rhachilla produced into a hairy bristle at the back of the palea, about ⅓ its length.—D. scabra, Buch. N.Z. Grasses, t. 26A (not of Benth.).
South Island: Otago — Swampy Hill (near Dunedin), Mount Pisa, Petrie! 1500–3500 ft. This was referred by Mr. Buchanan to D. scabra, Benth. (Agrostis scabra, R. Br.; Hook. f. Fl. Tasm. ii. 116, t. 160), which differs from the New Zealand plant, as indicated by Professor Hackel, in the small spikelets; scabrid branches of the panicle; in the flowering glume being almost as long as the empty ones, much more coriaceous and obtuse, and with fewer shorter hairs on the callus; in the very short awn inserted far above the middle of the back of the glume; and in the process of the rhachilla being shorter and less hairy. |